Yarn texturizing method and apparatus

ABSTRACT

METHOD AND APPARATUS FOR TEXTURIZING MULTI-FILAMENT THERMOSPLASTIC YARN. THE YARN IS FED INTO A YARN DELIVERY TUBE HAVING A TERMINAL END PROJECTING INTO A LARGER TUBE. THE LARGER TUBE TERMINATES AT A TEXTURIZING ZONE DEFINED BY THE BIGHT BETWEEN A PAIR OF OPPOSED MESH BELTS AS THEY PASS AROUND THEIR RESPECTIVE SUPPORT ROLLERS AND BY ADJUSTABLE PLATES CONTROLLING THE WIDTH OF THE ZONE. AIR UNDER PRESSURE AND WITH A SWIRLING MOTION IMPARTED THERETO IS FED INTO THE LARGER TUBE, THE AIR FLOWING THERETHROUGH TO THE TEXTURIZING ZONE AND DRAWING THE YARN THEREWITH AND CAUSING THE YARN TO TWIST AS IT LEAVES THE YARN DELIVERY TUBE. AS THE YARN REACHES THE TEXTURIZING ZONE THE SWIRLING CURRENT OF AIR CAUSES THE YARN TO FORM SPIRALS WHICH ARE CONFINED IN OVERLAPPING COMPACTED RELATIONSHIP AS   THEY ENTER THE BIGHT BETWEEN THE BELTS. DURING THE PASSAGE OF THE YARN BETWEEN THE BELTS IT IS SUBJECTED TO HEATING AND THEREAFTER TO COOLING. AFTER THE YARN LEAVES THE BELTS IT IS TENSIONED TO BULK THE YARN AND THE TENSION IS THEREAFTER RELAXED AND THE YARN WOUND INTO A PACKAGE.

Dec. 14, 1911 Filed may 1 1970 :TLE-

'A. J. CHUDGAR ETAL 3,626,557

YARN TEXTURIZING METHQD AND APPARATUS 3 Sheets-Sheet 1 Dec. 14, 1971CHUDGAR ETAL 3,626,557

YARN TEXTURIZING METHOD AND APPARATUS 5 Sheets-Sheet 2 Filed May 18,1970 Dec. 14, 1Y1 QHUDGAR ETAL 3&2555! YARN TEXTURIZING METHOD ANDAPPARATUS Filed May 18, 1970 5 Sheets-Sheet 5 United States Patent3,626,557 YARN TEXTURIZING METHOD AND APPARATUS Ashvin J. Chudgar andWalter R. Dunn, Reading, and Vincent A. Iannucci, West Lawn, Pa.,assignors to North American Rockwell Corporation, Pittsburgh, Pa.

Filed May 18, 1970, Ser. No. 37,995 Int. Cl. D02g 1/20 US. Cl. 281.3 13Claims ABSTRACT OF THE DISCLOSURE Method and apparatus for texturizingmulti-filament thermoplastic yarn. The yarn is fed into a yarn deliverytube having a terminal end projecting into a larger tube. The largertube terminates at a texturizing zone defined by the bight between apair of opposed mesh belts as they pass around their respective supportrollers and by adjustable plates controlling the width of the zone. Airunder pressure and with a swirling motion imparted thereto is fed intothe larger tube, the air flowing therethrough to the texturizing zoneand drawing the yarn therewith and causing the yarn to twist as itleaves the yarn delivery tube. As the yarn reaches the texturizing zonethe swirling current of air causes the yarn to form spirals which areconfined in overlapping compacted relationship as they enter the bightbetween the belts. During the passage of the yarn between the belts itis subjected to heating and thereafter to cooling. After the yarn leavesthe belts it is tensioned to bulk the yarn and the tension is thereafterrelaxed and the yarn wound into a package.

BACKGROUND OF THE INVENTION The instant invention relates to a methodand apparatus for modifying thermoplastic multi-filaments yarns.Heretofore man-made multi-filament thermoplastic yarns such for exampleas polymedic yarns including nylon, Orlon and Dacron, synthetic resinyarns such as phenolic and acrylic resin yarns, polypropylene yarns andyarns composed of organic derivatives of cellulose have been treated invarious ways to convert them into what is known in the art as texturedyarns. Such textured yarns as distinguished from the original yarns havegreatly improved absorbance and hand and depending upon the particularconversion method employed have bulk and/or stretch characteristics.

The known methods for producing textured yarn include the false twistmethod in which the yarn is twisted, heat set and then untwisted, theso-called edge crimping method in which the yarn is drawn at a sharpangle around an edged member under tension, the stutter boX method inwhich the yarn is compacted into a confined zone and then heat set, theknit deknit method in which the yarn is first knitted into a fabric,then heat set and thereafter the fabric unraveled or deknit, andvariations of said methods. The instant invention has for its principalobject the provision of method and apparatus for texturizingthermoplastic yarn the method being some what analogous to the methodheretofore employed such as the stulfer box method but which imparts tothe yarn a superior and substantially uniform texture and uniformdyeability.

SUMMARY OF THE INVENTION In accordance with the instant invention athermoplastic multi-filament yarn of any of the types referred to aboveis drawn from a supply thereof and delivered through a yarn deliverytube to a cylindrical tube-like member in which it is subjected to theaction of a swirling current of air traveling at high velocity in thedirection of movement of the yarn. The swirling air current within thetubelike member tends to distort and spread the filaments of the yarn,and imparts a certain degree of twist thereto. It also serves to drawthe yarn through the delivery tube. The tube-like member projects into atexturizing enclosure defined by the bite between a pair of opposed meshbelts as they pass around their respective end rollers, by top andbottom members defining the vertical dimension of the enclosure and byadjustably mounted side plates defining the width of the enclosure. Theside plates have opposed edges forming the enclosure side walls theedges converging in the direction of movement of the yarn to providewith the mesh belts a final restricted passageway or texturizing zonefor the yarn as it passes into the bits between the belts. As the yarnleaves the tube-like member it is drawn or forced forwardly by the airstream into the texturing zone the yarn at that point being formed intoa spiral or succession of coils by the swirling motion of the airstream. The width of the restricted passageway determines the amplitudeof the coils. As the coils enter the said nip between the belts they arepressed backwardly into overlapping relationship and confined andcompacted between the belts. The belts, traveling at a greatly reducedspeed as compared to the in-feed velocity of the yarn to the texturizingzone, carry the compacted yarn first through a heating Zone to heat setthe yarn in its compacted form and thereafter through a cooling zone. Asthe yarn leaves the belts it is drawn by a first set of draw-off rollswhich advance the yarn at a relatively high speed as compared to thespeed of the belts to extend the yarn to the extent that it approachesan uncoiled state and is then drawn by a second set of draw-off rolls atsomewhat higher speed. As the yarn leaves the second set of rolls it isallowed to relax and in consequence the filaments of the yarn separatethus imparting a bulked formation of the yarn.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic elevationalview of an apparatus for processing thermoplastic yarn in accordancewith the instant invention;

FIG. 2 is a top plan view on an enlarged scale as compared to FIG. 1 andwith parts broken away for clearness of illustration of the texturizingunit of the instant invention;

FIG. 3 is a sectional view taken on the line 33 of FIG. 2;

FIG. 4 is a sectional view on an enlarged scale taken on the line 44 ofFIG. 3;

FIG. 5 is a sectional view taken on the line 5-5 of FIG. 2; and

FIGS. 6 to 10 inclusive are magnified photographic views of a continuousmonofilament yarn as it appears at points in its processing indicated bythe arrows A to E respectively of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawingsand particularly to FIG. 1 there is disclosed an apparatus forprocessing a multifilament thermoplastic yarn Y in accordance with theinstant invention. The yarn Y may be of any of the compositionspreviously referred to as employed for texturized yarns or of othersuitable compositions. The yarn Y is supplied from a pirn 10 which isrotatably mounted on a suitable pirn holder 11 and is drawn from thepirn by a driven feed roll set 12. From the feed roll set the yarnpasses through a yarn texturizing unit indicated generally at 13 andWhich will be hereinafter described in detail and by which the yarn isdeposited in the form of overlapping spirals in the nip between endlessmesh belts 14 and 15 carried by end rolls 16, 17 and 18, 19 respectivelythe roll shafts being supported from a frame structure in suitablebearings (not shown). Rolls 16 and 18 have surface characteristics, suchas for example as peripheral grooves (-not shown), to permit air passingthrough the main belts at the nip therebetween to escape to theatmosphere. The mesh belts are driven to cause their adjacent runs,which lie in approximately contacting relationship, to travel in aforward direction but at greatly reduced speed as compared to the rateof delivery of the yarn by feed roll set 12.

Heaters 21 and 22 are supported in a suitable manner (not shown) onopposite sides of the adjacent runs of the mesh belts to heat set theyarn carried therebetween. Heaters 21 and 22 may be of any suitable typeas for example they may be in the form of metal platens positionedclosely adjacent the belts the platens being heated by electricalresistance units, by open flames or by other suitable means. Thetemperatures to which the platens are raised will depend upon the typeand denier of the yarn being processed, the effective heating length ofthe heaters and the like but in any event are such as to assure that theyarn will be heat set in its passage therepast. Cooling means isprovided forwardly of the heaters the cooling means suitably consistingof an upper hood 23 having an open mouth closely adjacent the upper sideof the lower run of the upper belt the hood being connected by conduit24 to any suitable source of air under pressure (not shown) and a lowerhood 25 having an open mouth adjacent the lower side of the upper run ofthe lower belt 15 connected by a conduit 26 to any suitable airexhaustion means (not shown) whereby cooling air may be passed throughthe adjacent runs of the mesh belt and the yarn being processed carriedtherebetween. The hoods may be supported in the positions described byany suitable means (not shown).

The yarn Y as it emerges from between the belts passes around a guideroll 27 and from the guide roll to a first godet roll set indicatedgenerally at 28 and comprising an upper idler roll 30 and a lower drivenroll 31. A second godet roll set indicated generally at 32 and includingan upper idler roll 33 and a lower driven roll 34 is positionedforwardly of roll set 28. The shafts of guide roll 27 and of the severalrolls of the godet roll sets are mounted in suitable bearings supportedby the frame structure (not shown).

A yarn spooler indicated generally at 35 is supported on a frame member36 the spooler including a core or spindle 37 mounted for free rotationin bearings in arms, one of which is shown at 38, pivotally carried byspaced brackets one of which is shown at 41. A driving roll 42 on whichthe spindle or a yarn body wound thereon rests is mounted for rotationis spaced arms 43-, one of which is shown in FIG. 1 the arms also beingcarried by bracket 41. A yarn traverse device 44 of any suitable type islocated in front of the nip between the driving roller and the spindlethe traverse device being reciprocated to wind the yarn on the spindlein a conventional manner by any suitable means (not shown).

Feed roll set 12, the supporting rolls for the mesh belts 14 and 15,rolls 31 and 34 and driving roll 42 may be driven from a common sourcesuch as a motor 45 through a line shaft 46 and associated drive means47, 48, 49, 50, 51 and 52 respectively, all indicated diagrammatically.As heretofore pointed out the relationship between the drive of feedroll set 12 and mesh belts 14 and 15 is such that the latter travel at agreatly reduced speed as compared to the infeed of the yarn. As forexample the speed ratio may be of the order of 30 to 1. With respect tobelts 14 and 15, the godet roll sets 28 and 32, and the driving roll 42of spooler 35 the relative speeds of operation are such that godet rollset 28 advances the yarn at a greatly enhanced rate as compared to therate of its delivery by the belts, as for example the ratio may be ofthe order of 24 to 1, godet roll set 32 advances the yarn at a higherspeed than godet roll set 28 as for example the ratio may be of theorder of 1.05 to 1, and the ratio of travel of the yarn is reducedbetween godet roll set 32 and the spooler 35 as for example the speedratio between the rate of delivery of the yarn by roll set 32 and itsrate of windup may be of the order of 1 to 0.95. It will be understoodhowever that one or more of the various speed ratios of yarn travel maybe altered depending upon various features as for example the amplitudeof the spirals in which the yarn is laid in the nip of the conveyor, thedesired properties of the textured yarn, and the denier of the yarnemployed.

Referring now particularly to FIGS. 2 to 5 inclusive the texturizingunit indicated generally at 13 and previously referred to will bedescribed in detail. The unit includes a tubular member 55 the hollowinterior of which is closed at the forward end by a preferably integralwall 56 and at the rearward end by a cap 57 suitably threaded ontomember 55 and confining a gasket 58 between the end of member and thecap. A liner 60 is mounted with in member 55 the liner including atransverse wall 61 dividing the interior thereof into a relatively longchamber 62 and a relatively short chamber 63. A yarn delivery tube 64having a bore of a diameter to readily accommodate the yarn to bedelivered therethrough extends from a point externally of member 55 andrelatively adjacent to feed roll set 12 through cap 57, gasket 58 andtransverse wall 61 and in air tight relationship therewith and through abore 65 in forward wall 56 the bore being of enlarged diameterrelatively to the tube to provide an annular air passagewaytherebetween. A tube 66 connected by a conduit 67 to any suitable sourceof air under pressure (not shown) has a terminal end secured in alignedbores in the walls of member 55 and liner 60 the tube communicating withthe interior of chamber 62. As illustrated particularly in FIGS. 3 and 4transverse wall 61 of liner 60 is provided with air passageways 68 and70 at opposite sides of yarn delivery tube 64 the air passagewaysproviding communication between chambers 62 and 63 and extending fromchamber 62 in downwardly and upwardly inclined directions respectivelywith respect to the delivery tube.

Tubular member 55 is supported on a bracket 71 carried by the machineframe the supporting means including a cap member 72 aifixed to thebrackets as by screws 73 (see FIG. 2). The tubular member is adapted foraxial adjustment and may be secured in any adjusted position as by setscrew 74. A tube 75 which may be integral with member 55 or attachedthereto in any suitable way has a bore of the same diameter as that of,and in alignment with, bore 65 in end wall 56. Tube 75 projects into atexturizing enclosure defined in part by a U-shaped member forming topand bottom walls 76 and 77 and an integral end wall 78 the latter beingbored for the extension of tube 75 therethrough in airtight relationshiptherewith. The U-shaped member is secured to and supported by a bracket89 forming a portion of the framework. A spacer washer 79 surrounds tube75 and fills the gap between end wall 78 and member 55. Walls 76 and 77include forward edges lying closely adjacent to mesh belts 14 and 15respectively, as they pass around their respective end rolls 16 and 18,the edges being contoured to conform to the contour of the belts. Thetexturizing enclosure is additionally defined by side plates 80 and 81of a thickness to fit between walls 76 and 77 and of a width to extendfrom rear wall 78 into the nip between the belts to the point 82 (seeFIG. 3). The forward edges of the plates are contoured similarly as theforward edges of walls 76 and 77 to conform to the contour of the belts.The inner end walls 83 and 84 of plates 80 and 81 respectively divergein a forward direction from a relatively wide spacing at their rear endsto a relatively narrow spacing at point 85 and thereafter continue toconverge but at lesser angles to point 82. The side plates are mountedfor adjustment relatively toward and away from each other to vary thewidth of a texturizing zone 86 defined by the forward edges of theplates and the mesh belts and are adapted to be secured in theiradjusted positions by studs 87 passing through elongated slots 88 in theplates the studs being threaded into portions of the framework. Tube 75projects into the texturizing enclosure to a point adjacent thetexturizing zone. Yarn delivery tube 64 projects into tube 75 and liescentrally thereof to define an annular air passageway therebetween, tube64 terminating at a point substantially rearwardly of the forward end oftube 75 as illustrated.

The operation of the apparatus described above in carrying out themethod of the instant invention will now be described. The yarn employedfor the purpose of the description is a polyester yarn of 150 denier andhaving 34 filaments, the yarn having substantially no twist. In settingup the apparatus for operation yarn Y is initially drawn from pirn andthreaded between feed rolls 12 and through yarn delivery tube 64 andtube 75 to the nip between the conveyor belts. Air under a pressure ofapproximately 80 pounds per square inch is then supplied through conduit67 to chamber 62. The drive mechanism for the several driven elements isso adjusted that upon energization of motor 45 feed roll set 12 advancesthe yarn at a velocity of the order of 500 yards per minute and belts 14and 15 advance their adjacent runs at a speed of the order of 17.0 yardsper minute. The adjustment of the drive mechanism is also such thatgodet roll set 28 will advance the yarn at a velocity of the order of400 yards per minute, godet roll set 32 will advance the yarn at avelocity of the order of 500 yards per minute and the driving roll 42 ofthe yarn spooler will cause the yarn to be wound into a package at arate of 490 yards per minute. Heaters 21 and 22 are activated to raisethe temperature of the yarn in its passage between belts 14 and 15 toapproximately 400 degrees F. to heat set the yarn and air is circulatedthrough the cooling means comprising upper and lower hoods 23 and 25respectively to reduce the temperature of the yarn substantially belowthat required for setting as the belts convey it past the cooling means.

In the operation of the apparatus air under pressure entering chamber 62moves through passageways 68 and 70 to chamber 63 and due to theangularity of the passageways adopts a swirling motion in chamber 63. Asthe air thereafter passes from chamber 63 into the relatively smallannular passageway defined by the outer diameter of yarn delivery tube64 and the inner diameter of tube 75 the rapidity of its swirling motionand its velocity of forward movement are both greatly increased. As theair stream passes beyond the end of the delivery tube and during itscontinued travel in tube 75 it grasps the yarn and due to its velocityand swirling motion it draws the yarn from the tube at the ratepermitted by roll set 12 and imparts twist to the yarn. Also theturbulence of the air stream tends to separate and distort individualfilaments of the yarn. As the yarn carried in the air stream emergesfrom the forward end of tube 75 and enters into texturizing zone 86 theswirling action of the air stream imparts a spiral formation to the yarnthe diameter of the coils of which are determined by the spacing of sideplates 80 and 81. The coils of the spiraled yarn as they enter the nipdefined by the mesh belts are forced backwardly to lie in overlappingcompacted relationship as illustrated in FIG. 3 and are maintained insuch condition as they pass between the belts. It will be understoodthat due to the high rate of delivery of the yarn to texturizing zone 86as compared to the rate of removal of the yarn by the belts a relativelydensified yarn mass results. As the yarn is carried by the belts pastheaters 21 and 22 the yarn is heat set and is thereafter cooled by thecirculation of air therethrough.

The appearance of the yarn layer as it emerges from between the belts isillustrated in photographic view FIG. 6 the latter having been taken atthe position indicated by the arrow A. Referring particularly to FIG. 1due to the relatively rapid draw-off rate of the yarn by godet roll set28 as compared to its delivery by belts 14 and 15, the yarn is greatlydrawn out or extended during its travel from the belts to the roll set.The yarn when it reaches the point indicated by the arrow B is extendedto the point that its spiral formation becomes apparent as illustratedin photographic view FIG. 7. Upon further travel of the yarn to thepoint indicated by arrow C its extension is such that it has theappearance illustrated by photographic view FIG. 8. The furtherextension of the yarn as it is drawn at a still higher rate of travel bygodet roll set 32 produces the formation illustrated by photographicview FIG. 9 taken at the point indicated by arrow D. Thereafter and dueto the relatively lower speed of windup of the yarn as it is packaged ascompared to its rate of delivery by godet roll set 32, the yarn relaxesand bulks to impart to it the characteristics illustrated byphotographic view FIG. 10 the view being taken at approximately thepoint indicated by the arrow B in FIG. 1.

It will be understood that the particular character or configuration ofthe yarn in the completed form as illustrated in FIG. 10 may be variedin a number of ways. For example the diameter of the coils into which itis formed in the texturizing zone may be increased or decreased asdesired by adjustment of said plates and 81. Also air under a differentpressure than that previously stated may be supplied to chamber 62. Inaddition the rate of yarn feed relatively to the rate of travel of belts14 and 15 may be varied to produce different effects.

Having thus described the invention in rather complete detail it will beunderstood that these details need not be strictly adhered to and thatvarious changes and modifications may be made all falling within thescope of the invention.

What is claimed is:

1. A method of processing thermoplastic multi-filament yarn whichcomprises drawing said yarn from a supply thereof, subjecting said yarnto a swirling stream of air to form a continuous series of coilstherein, delivering said coils of yarn to a confined texturizing zone,mechanically compressing said coils into overlapping relationship, andheating and thereafter cooling said compressed coils of yarn whilecontinuing to hold them in mechanical compression.

2. A method as defined in claim 1 wherein said yarn following saidheating and cooling operations is subjected to tension to separate theoverlapped coils thereof.

3. A method as defined in claim 2 wherein said yarn, following saidseparation of the overlapped coils thereof, is subjected to furthertension to cause the separation of the individual filaments withattendant bulking of the yarn.

4. A method as defined in claim 1 wherein said causing of the yarn toform coils thereof is obtained by subjecting said yarn to a whirling airstream.

5. A method as defined in claim 4 wherein said air stream additionallyserves to advance said yarn to said texturizing zone.

6. An apparatus for processing thermoplastic multifilament yarn duringits travel in a forward direction comprising a yarn delivery tube havinga yarn delivery end, a tube of enlarged diameter relative to saiddelivery tube surrounding the latter at the yarn delivery end thereofand extending forwardly therefrom and terminating in an open end, meanssurrounding said open end defining a yarn texturizing zone said meansincluding opposed endless belts supported to provide a nip therebetween,means for advancing said belts in said forward direction and means forsupplying a whirling and forwardly moving air stream in said tube ofenlarged diameter to advance sa d yarn to said texturizing zone and,upon the issuance of said air stream from said tube of enlargeddiameter, to form spiral convolutions of said yarn at said nip betweensaid rolls.

7. An apparatus as defined in claim 6 wherein said means for supplyingthe whirling and forwardly moving air stream comprises a first airchamber, means for supplying air under pressure to said first airchamber, a second air chamber, inclined air inlet passages connectingsaid first and second chambers and an outlet in said second chamberdefining with said yarn delivery tube an annular air passageway to saidtube of enlarged diameter.

8. An apparatus as defined in claim 7 wherein said first and second airchambers are separated by a dividing wall which is penetrated by saiddelivery tube substantially centrally thereof and wherein said air inletpassages comprise a pair of passageways through said walls on oppositesides of said delivery tube and inclined in opposite directions fromeach other.

9. An apparatus as defined in claim 6 wherein there is means to advancesaid endless belts to cause said yarn convolutions to be compacted inoverlapping relationship within said nip and to be carried between saidbelts and there is means to heat set said yarn as it is carried betweensaid belts.

10. An apparatus as defined in claim 9 wherein there is means to controlthe rate of feed of yarn to said yarn delivery tube.

11. An apparatus as defined in claim 9 wherein there is a first draw-offmeans to advance said yarn as it issues from between said belts at ahigher speed than the rate of advance of said endless belts to separatethe overlapped convolutions thereof.

12. An apparatus as defined in claim 11 wherein there is a seconddraw-off means forwardly of said first drawoff means to advance saidyarn at a higher speed than said first draw-off means to causeseparation of the individual filaments thereof with attendant bulking ofsaid yarn.

13. An apparatus as defined in claim 9 wherein there is means locatedadjacent said belts to cool said yarn after it has been heat set.

References Cited UNITED STATES PATENTS 2,938,258 5/1960 Starkie 28 1.63,044,145 7/1962 Tager et al. 28-16 3,058,167 10/1962 Rainard et al.28-1.6 3,247,567 4/1966 Hartmann 28-l.6 3,303,546 2/1967 Van Blerk28-1.3 3,389,445 6/1968 Schrefiler 281.3 3,482,294 12/1969 Joly 281.6

LOUIS K. RIMRODT, Primary Examiner US. Cl. X.R.

